A 19-year-old man and his mother have been remanded in custody on murder charges after the stabbing death of a Sydney policeman.

Mitch and Fiona Barbieri have been charged over the death of Detective Inspector Bryson Anderson, who died in Hawkesbury District Hospital in Windsor after being stabbed at a property in Oakville, in Sydney's north-west, yesterday afternoon.

Inspector Anderson was one of several officers called to the property to deal with a dispute between neighbours.

Police say two hours of negotiations broke down and the detective was stabbed.

The Barbieris, aged 19 and 45, were charged this morning.

They were not brought to the dock at Penrith Local Court and did not apply for bail. They will remain behind bars until their next court appearance in a week's time.

In a charge sheet tendered to the court, police listed their reasons for keeping the pair in custody overnight, saying they have shown no remorse and are in complete denial of the offence.